//
//  QGNewFeatureView.swift
//  斯威夫特微博
//
//  Created by youyoumacmini3 on 2017/7/18.
//  Copyright © 2017年 youyoumacmini3. All rights reserved.
//

import UIKit


/// 新特性视图
class QGNewFeatureView: UIView {

    @IBOutlet weak var scrollView: UIScrollView!
    @IBOutlet weak var enterButton: UIButton!
    @IBOutlet weak var pageControl: UIPageControl!
    
    // 进入微博
    @IBAction func enterStatus() {
        removeFromSuperview()
    }
    
 
    class func newFeatureView() -> QGNewFeatureView {
        
        let nib = UINib(nibName: "QGNewFeatureView", bundle: nil)
        let v = nib.instantiate(withOwner: nib, options: nil)[0] as! QGNewFeatureView
        
        v.frame = UIScreen.main.bounds
        
        return v
    }
    
    override func awakeFromNib() {
        
        // 如果使用自动布局设置的界面，从xib加载默认是600 * 600大小
        // 添加4个图像视图
        
        let count = 4
        let rect = UIScreen.main.bounds
        
        for i in 0..<count {
            let imageName = "new_feature_\(i + 1)"
            let iv = UIImageView(image: UIImage(named: imageName))
            
            // 设置大小
            iv.frame = rect.offsetBy(dx: CGFloat(i) * rect.width, dy: 0) 
            scrollView.addSubview(iv)
        }
        // 指定 scrollView属性
        scrollView.contentSize = CGSize(width: CGFloat(count + 1) * rect.width, height: rect.height)
        scrollView.bounces = false
        scrollView.isPagingEnabled = true
        scrollView.showsVerticalScrollIndicator = false
        scrollView.showsHorizontalScrollIndicator = false
        
        scrollView.delegate = self
        // 隐藏按钮
        enterButton.isHidden = true
    }
}

extension QGNewFeatureView: UIScrollViewDelegate {
    
    func scrollViewDidEndDecelerating(_ scrollView: UIScrollView) {
        // 1. 滚动到最后一屏让视图删除
        let page = Int(scrollView.contentOffset.x / scrollView.bounds.width)
        //print(page)
        
        // 2. 判断是否最后一页
        if page == scrollView.subviews.count {
            print("删除")
            removeFromSuperview()
        }
        
        // 3. 如果是倒数第二页显示按钮
        enterButton.isHidden = page != scrollView.subviews.count - 1
        
    }
    
    func scrollViewDidScroll(_ scrollView: UIScrollView) {
       
        // 0. 一旦滚动隐藏按钮
        enterButton.isHidden = true
        
        
        // 1. 计算当前偏移量
        let page = Int(scrollView.contentOffset.x / scrollView.bounds.width + 0.5)
        print(page)
        
        // 2. 设置分页控件
        pageControl.currentPage = page
        
        // 3. 分页控件隐藏
        pageControl.isHidden = page == scrollView.subviews.count
    }
    
}





